Orca Offshore performed transport and installation analyses for Centrica’s GBP self-installing gas platform in the Dutch North Sea. The

F3-FA platform has a suction pile foundation resting on a temporary barge for transportation. It can be relocated, providing significant cost
savings across three to four fields. Orca’s scope of work included motion and stability analysis, multi-body dynamic analysis, structural
spectral analysis, and scale model tests.

It was crucial to know hydrodynamic loads early in the project due to the pile size – 15 meters high and 15 meters in diameter – and
proximity to the wave zone. The loads determined how to size the steel work. MOSES determined those loads and the wave clearances
required to confirm the structural strength of the platform. The use of MOSES reduced the amount of steel required in the platform and for
sea fastening and proved that this unique, reusable platform concept would work.

Orca Offshore | Dutch North Sea, Netherlands

Centrica F3-FA Self-installing Platform FINALIST

Statoil awarded SNC-Lavalin the front-end engineering design contract for its massive 22,000-ton jacket at the USD 7 billion Mariner oil
field development in the U.K. sector of the North Sea. With an 88-by- 62 meter footprint on the seabed, the 120-meter-high jacket supports
a topside facility weighing approximately 54,000 tons. The jacket’s weight and subsequent installation by barge were significant challenges.

Using SACS and STAAD.Pro, SNC-Lavalin completed the jacket design in a tight timeframe. Nineteen interrelated analyses were performed
effectively using SACS’ various modules, including wave-loading under storm conditions, seismic response, fatigue, sea-transportation,
and accidental impact. STAAD.Pro was used for the detailed design of secondary steel. Working with the same software as the topsides
designer enabled efficient information sharing and modeling of the interfaces between jacket and topsides.